Internal-combustion engine



FIG. 1 is a side perspective view of the internal-combustion engine.

FIG. 2 is a left side view of the internal-combustion engine.

FIG. 3 is a right side view of the internal-combustion engine.

FIG. 4 is a rear view of the internal-combustion engine.

FIG. 5 is a front view of the internal-combustion engine; and,

FIG. 6 is a bottom view of the internal-combustion engine. 

The ornamental design for an internal-combustion engine, as shown and described. 